In the production of hydrocarbons from subsurface formations, it is common to use a sucker rod to lift fluids to the surface. Typical sucker rod pumps include a string of sucker rods extending from the earth's surface down to a downhole pump. A pump jack located on the surface is employed to reciprocate the sucker rod string and thus the downhole pump. The pump jack typically is a beam that pivots in a vertical plane and which is provided with a horse head at one end. The horse head supports a pair of bridle cables and a carrier bar.
A polished rod is suspended from the carrier bar and extended through a stuffing box. The lower end of the polished rod is attached to the upper end of the sucker rod string. The polished rod has a polished exterior surface to serves to form a seal with the stuffing box and thus force formation fluid that is lifted to the earth's surface to flow from production tubing to a collection conduit by which the produced fluid is conveyed to a tank battery, pipeline or other system whereby the produced fluid is collected.
The sucker rod string is formed of a series of individual sucker rods which are connected to one another in an end-to-end fashion so as to work together to lift the fluid from the ground. At times, the need arises to service the well or replace or maintenance the downhole pump. To do so requires the sucker rod string be removed from the well.
Removal of the sucker rod string starts with the removal of the polished rod. Because polished rods are manufactured with a smooth, polished shaft having a uniform diameter, a pony rod is typically attached to the upper end of the polished rod to provide a location at which a rod elevator can be attached. Pony rods are provided with a recessed section consisting of a smaller diameter than the diameter at its ends. This recessed section allows the rod elevator to be attached to the pony rod so that the rod string can be lifted from the well.
After the polished rod is lifted and detached from the sucker rod string, the remaining sucker rods in the rod string are removed without the assistance of a pony rod because the sucker rods have a latching area for the rod elevator. Thus, only the polished rod requires the use of the pony rod to facilitate its removal from the rod string. Conventional rod elevators include a C-shaped or U-shaped body defining a rod receiving space. Two latch members are pivotally attached to the body to close on a rod automatically to securely lock the rod within the body. The rod can be released by thumb and finger pressure at either the front or rear of the body. A bail is connected to the body. The bail is a generally arched structure to permit the rod elevator to be suspended from a hook.
In practice, the rod elevator is suspended from a hook that is attached to the traveling block of a block and tackle assembly (i.e., an external hoist). During the process of connecting the rod elevator to the polished rod, the traveling block is typically positioned near the horsehead of the pump jack. Depending on the position of the horsehead and the traveling block, a problem may be encountered connecting the rod elevator to the polished rod due to contact between the horsehead and the traveling block interfering with the positioning of the rod elevator on the polished rod. For the foregoing reasons, there is a need for an apparatus that prevent contact between the horsehead and traveling block thereby facilitating a safe and efficient positioning of the rod elevator on the polished rod.